Further investigate recursion depth and associated mem-consumption

[liamsi]

Not too long ago the code snippet below produced a 100KB JSON message which consumed about 1,3 Gb memory while decoding.

package main
import (
"strings"
"github.com/tendermint/go-amino"
)
type Tree struct {
    Value int  `json:"v"`
    Children []Tree `json:"c"`
}
func main() {
    approxTargetLen := 100000
    msgBegin := `{"v":1,"c":[`
    msgEnd := `]}`
    repeatCnt := int(approxTargetLen / (len(msgBegin) + len(msgEnd)))
    recurMsg := strings.Repeat(msgBegin,repeatCnt )
    recurMsg = strings.Join([]string{recurMsg,strings.Repeat("]}",repeatCnt)},"")
    cst := Tree{}
    cdc := amino.NewCodec()
    cdc.UnmarshalJSON([]byte(recurMsg), &cst)
}

Although this is not the case anymore (it only consumes 45 Mb), we should make sure that we either use less recursion or limit the recursion depth (or fully understand why this isn't necessary anymore).

[ValarDragon]

ref #197